Convertitor

package dibello.paolo.test;


import android.app.Activity;
import android.R.*;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.TextView;
import android.widget.Toast;


public class MainActivity extends Activity {

    EditText ed1;
    TextView resu;
    Button btn;
    RadioButton ce_to_fa,fa_to_ce;



    @Override
    protected void onCreate(Bundle savedInstanceState) {//Start of oncreate
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main); //Call layout

        //***Call View IDs allway before do some stuff with them
        ed1=(EditText)findViewById(R.id.editText);

        resu=(TextView)findViewById(R.id.textView);

        ce_to_fa=(RadioButton)findViewById(R.id.radioButton);
        fa_to_ce=(RadioButton)findViewById(R.id.radioButton2);

        btn=(Button)findViewById(R.id.button);

        //***Call View IDs end!

       show_toast("Ciao, guarda come sono educato!");

        btn.setOnClickListener(new View.OnClickListener() { //Start button click
            @Override
            public void onClick(View view) {

                if(ed1.length()==1||ed1.length()>1){
                    int a = Integer.parseInt(ed1.getText().toString()); //This is textbox one
                    if(fa_to_ce.isChecked()){
                        resu.setText(Double.toString((a-32.0) * 5.0/9.0)); //Show result to textview

                    }else(ce_to_fa.isChecked()){
                        resu.setText(Double.toString((a*9.0)/5.0+32.0)); //Show result to textview

                    }


                }else{
                    if(ed1.length()==0){
                       //now i call show_toast and paste message there
                        show_toast("Scrivere, casella vuota");
                    }

                }
            }
        });

    }

    public void show_toast(String message){
        Toast.makeText(MainActivity.this,
                message, Toast.LENGTH_LONG).show();
    }
}